Emulsion explosive composition based on hydrogen peroxide and nitrate

ABSTRACT

Proposed is an emulsion explosive composition containing 80% to 95% by weight of an oxidizing agent aqueous solution containing hydrogen peroxide, nitrate, and diethylene triamine penta(methylene phosphonic acid) (DTPMPA), 0.1% to 10% by weight of an emulsifier, and 2% to 15% by weight of an oil. The emulsion explosive composition can effectively solve self-gassing problems caused by a reaction between hydrogen peroxide and nitrate.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2022-0047302, filed Apr. 18, 2022, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure The present disclosure relates to an emulsion explosive composition based on hydrogen peroxide and nitrate. 2. Description of the Related Art

Emulsion explosives, first developed in the 1960s, are explosives that are currently widely used around the world. Currently available emulsion explosives are based on ammonium nitrate, which inevitably generates toxic NOx gas after blasting. Recently, increasing interest in the environment and the issue of blasting pollution have led to the development of NOx-free products that can fundamentally remove NOx gas. In addition, explosives using hydrogen peroxide as an oxidizing agent, instead of ammonium nitrate, have been developed.

Since then, research on the composition using nitrate and hydrogen peroxide as oxidizing agents has been conducted. Compared to products using only hydrogen peroxide, a wide range of specific gravity is available, thereby extending the range of available energy and enabling selective use of the power of gunpowder depending on the usage environment.

In addition, the advantages of reducing NOx gas generation, compared to existing ammonium nitrate-based emulsions, while partially compensating for the low energy generated when using only hydrogen peroxide as an oxidizing agent can be obtained (I. Fullelove, M. Araos & I. Onederra, Detonation performance of novel hydrogen peroxide and nitrate based hybrid explosives (2017)).

However, hydrogen peroxide-based emulsion to which nitrate is added undergoes a self-gassing reaction in which hydrogen peroxide and nitrate react and are decomposed due to the high reactivity of hydrogen peroxide, thereby generating O₂ gas, particularly the self-gassing reaction being promoted at a temperature of 30° C. or higher.

Therefore, there is a demand for developing technologies capable of solving the above self-gassing problem.

SUMMARY OF THE INVENTION

The present disclosure has been made to solve the above problems of the related art, and an objective of the present disclosure is to provide an emulsion explosive composition based on hydrogen peroxide and nitrate capable of being stably and safely used by improving self-gassing problems.

The present disclosure provides an emulsion explosive composition containing: 80% to 95% by weight of an oxidizing agent aqueous solution containing hydrogen peroxide, nitrate, and diethylene triamine penta(methylene phosphonic acid) (DTPMPA); 0.1% to 10% by weight of an emulsifier; and 2% to 15% by weight of an oil.

An emulsion explosive composition of the present disclosure can solve self-gassing problems of an emulsion explosive composition based on hydrogen peroxide and nitrate, thereby enabling the explosive emulsion to be stably and safely used.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, the present disclosure will be described in detail. An emulsion explosive composition of the present disclosure contains: 80% to 95% by weight of an oxidizing agent aqueous solution containing hydrogen peroxide, nitrate, and diethylene triamine penta(methylene phosphonic acid) (DTPMPA); 0.1% to 10% by weight of an emulsifier; and 2% to 15% by weight of an oil.

Emulsion explosive compositions based on hydrogen peroxide and nitrate have a disadvantage in that safety and stability are deteriorated due to self-gassing, in which hydrogen peroxide and nitrate react and are decomposed, thereby generating O₂ gas due to the high reactivity of hydrogen peroxide. The present disclosure is characterized by minimizing such self-gassing problems.

The oxidizing agent aqueous solution may contain 10% to 45% by weight of the hydrogen peroxide, 10% to 50% by weight of the nitrate, 0.1% to 15% by weight of the DTPMPA, and 10% to 45% by weight of water.

In the above numerical range, 0.1% to 10% by weight of the DTPMPA is preferably contained, and 0.5% to 5% by weight of the DTPMPA is more preferably contained.

In the present disclosure, the amount of the hydrogen peroxide is described based on the concentration of 100%.

The nitrate may include at least one selected from the group consisting of ammonium nitrate, calcium nitrate, sodium nitrate, magnesium nitrate, and the like, and sodium nitrate is preferably used.

80% to 95% by weight of the oxidizing agent aqueous solution is contained with respect to the total weight of the emulsion explosive composition. When the composition ratio of the oxidizing agent aqueous solution exceeds 95% by weight, a problem in that the emulsion is not prepared may occur. On the contrary, when the composition ratio of the oxidizing agent aqueous solution is less than 80% by weight, a problem of non-detonation may occur.

In one embodiment of the present disclosure, the emulsion explosive composition may further contain 0.1% to 10% by weight of an oil thickener. The oil thickener may be contained by being added to an oil composition. In the above numerical range, 2% to 10% by weight of the oil thickener is preferably contained, and 3% to 10% by weight of the oil thickener is more preferably contained.

The oil thickener may include at least one selected from the group consisting of hydrogenated palm oil, glucamate, cetyl alcohol, polyquarter, and the like.

The emulsion explosive composition of the present disclosure containing the oil thickener may have a viscosity in a range of 10,000 cP to 300,000 cP, preferably, in the range of 50,000 cP to 200,000 cP, and more preferably, in the range of 65,000 cP to 100,000 cP.

In one embodiment of the present disclosure, the emulsifier may include at least one selected from the group consisting of sorbitan monooleate (SMO), amine salt of polyisobutylene succinic anhydride (PIBSA), and the like, but is not limited thereto.

The emulsifier preferably includes an emulsifier containing PIBSA amine salt having a flash point of 100° C. or higher, an acid value of 7 to 8, and an amine value of 40 to 60.

In one embodiment of the present disclosure, the oil may include at least one selected from the group consisting of fuel oil, oil, and the like.

The fuel oil may include at least one selected from the group consisting of wax, mineral oil, light oil, and the like. Preferably, carbonaceous fuel oil that is liquefied at a temperature in a range of 50° C. to 80° C. is used as the fuel oil.

The oil may include at least one selected from among mineral oil, lubricating oil, and the like.

In one embodiment of the present disclosure, the emulsion explosive composition may further contain plastic micro bubbles (PMBs) or glass micro bubbles (GMBs). 0.1% to 10% by weight of the PMBs or GMBs may be contained with respect to the total weight of the composition.

In one embodiment of the present disclosure, the emulsion explosive composition may further contain KMnO₄. 0.0001 to 1% by weight of the KMnO₄ may be contained with respect to the total weight of the composition.

When adding the nitrate to the hydrogen peroxide in the emulsion explosive composition of the present disclosure, the energy can be increased as follows. In addition, since the specific gravity of the emulsion is higher than that of an emulsion using only hydrogen peroxide, a wider range of specific gravity is available depending on the content of a sensitizer. As a result, the scope of gunpowder energy also broadens, so the power of gunpowder is selectively available depending on the nature of the applied field.

Emulsion based Emulsion based Emulsion based on hydrogen on H₂O₂ and on sodium Classification peroxide sodium nitrate nitrate Available energy 1,687-2,076 1,714-2,239 1,789-2,381 (100 MPa), KJ/kg Density (g/cc) 0.80-1.14 0.80-1.25 0.80-1.35

Hereinafter, the present disclosure will be described in more detail through examples. However, the following examples are intended to explain the present disclosure in more detail, and the scope of the present disclosure is not limited by the following examples. The following examples may be appropriately modified or changed by those skilled in the art within the scope of the present disclosure.

Example 1: Preparation of Emulsion Explosive

An oxidizing agent aqueous solution was prepared by mixing 33% by weight of hydrogen peroxide, 30% by weight of sodium nitrate, 4% by weight of diethylene triamine penta(methylene phosphonic acid) (DTPMPA), and 33% by weight of water.

In another container, a fuel solution containing 90% by weight of light oil and 10% by weight of an emulsifier was heated to a temperature of 50° C. or higher and then uniformly mixed.

Next, an emulsion explosive composition was prepared by mixing 90% by weight of the oxidizing agent aqueous solution and 10% by weight of the fuel solution, prepared above, in a mixer.

Example 2: Preparation of Emulsion Explosive

An oxidizing agent aqueous solution was prepared by mixing 33% by weight of hydrogen peroxide, 30% by weight of sodium nitrate, 4% by weight of diethylene triamine penta (methylene phosphonic acid) (DTPMPA), and 33% by weight of water.

In another container, a fuel solution containing 87% by weight of light oil, 10% by weight of an emulsifier, and 3% by weight of an oil thickener (trade name: Dermofeel Viscolid MB, manufacturer: EVONIK) was heated to a temperature of 50° C. or higher and then uniformly mixed.

Next, an emulsion explosive composition was prepared by mixing 90% by weight of the oxidizing agent aqueous solution and 10% by weight of the fuel solution, prepared above, in a mixer.

Example 3: Preparation of Emulsion Explosive

An emulsion explosive was prepared by compounding 99.9% by weight of the emulsion explosive composition prepared in Example 1 and 0.1% by weight of a KMnO₄ solution having a concentration of 0.1%, using a mixer.

Example 4: Preparation of Emulsion Explosive

99.5% by weight of the emulsion explosive composition prepared in Example 1 and by weight of PMB (a copolymer of VDC containing 50% ACN, ACN, and MMA having a true specific gravity (d) of 0.02) were mixed using a mixer to prepare an emulsion explosive.

Comparative Examples 1 to 5: Preparation of Emulsion Explosives

PPAN-containing emulsion explosive compositions were prepared in the same manner as in Example 1, except that the usage of DTPMPA in Example 1 was set to 0, or DTPMPA was replaced with components specified in Table 1, known as hydrogen peroxide stabilizers.

TABLE 1 Hydrogen peroxide stabilizer Example 1 DTPMPA Comparative Example 1 not added Comparative Example 2 HEDP Comparative Example 3 Oil thickener Comparative Example 4 Polyquarter Comparative Example 5 Sodium phytate Note) HEDP: 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid

Experimental Example 1: Evaluation of self-gassing volume increase rate of emulsion explosive composition

Each of the emulsion explosive compositions prepared in Example 1 and Comparative Examples 1 to 5 was put into a graduated cylinder to evaluate a volume increase rate caused by a self-gassing reaction at room temperature. The results thereof are shown in Table 2.

TABLE 2 Volume increase rate Hydrogen peroxide stabilizer Day 3 Day 7 Example 1 DTPMPA  5% 10% Comparative not added 19% 48% Example 1 Comparative HEDP 15% 85% Example 2 Comparative Oil thickener  9% 27% Example 3 Comparative Polyquarter 18% 36% Example 4 Comparative Sodium phytate 13% 25% Example 5

From Table 2, it was confirmed that the emulsion explosive composition prepared in Example 1, in which diethylenetriamine penta(methylene phosphonic acid) (DTPMPA) was added to the aqueous oxidizing agent solution, had a remarkably excellent self-gassing inhibitory effect compared to the emulsion explosive composition without DTPMPA (Comparative Example 1) and the emulsion explosive compositions (Comparative Example 2-4) including other components, known as the hydrogen peroxide stabilizers.

Experimental Example 2: Evaluation of Self-Gassing Volume Increase Rate According To Viscosity Of Emulsion Explosive Compositions

The temperature-dependent volume increase rates of the emulsion explosive compositions prepared in Example 1 (having a viscosity of 28,000 cP) and Example 2 (including an oil thickener and having a viscosity of 70,000 cP) were evaluated on day 3 and day 7. The results thereof are shown in Table 3 below.

TABLE 3 Example 2 Viscosity of Example 1 70,000 cP Viscosity of Room 28,000 cP temperature Classification 40° C. (20° C.) 30° C. 40° C. Volume Day 3 13% 0% 0%  1% increase rate Day 7 41% 0% 9% 17%

From Table 3, it was confirmed that self-gassing was further significantly inhibited even at high temperatures in the case of the high-viscosity emulsion explosive composition containing the oil thickener in the fuel solution. 

What is claimed is:
 1. An emulsion explosive composition comprising: 80% to 95% by weight of an oxidizing agent aqueous solution comprising hydrogen peroxide, nitrate, and diethylenetriamine penta(methylene phosphonic acid) (DTPMPA); to 10% by weight of an emulsifier; and 2% to 15% by weight of an oil.
 2. The composition of claim 1, wherein the oxidizing agent aqueous solution comprises: 10% to 45% by weight of the hydrogen peroxide; 10% to 50% by weight of the nitrate; to 15% by weight of the DTPMPA; and 10% to 45% by weight of water.
 3. The composition of claim 1, wherein the nitrate comprises at least one selected from the group consisting of ammonium nitrate, calcium nitrate, sodium nitrate, and magnesium nitrate.
 4. The composition of claim 1, further comprising 0.1% to 10% by weight of an oil thickener comprising at least one selected from the group consisting of hydrogenated palm oil, glucamate, cetyl alcohol, and polyquarter.
 5. The composition of claim 1, further comprising a plastic micro bubble (PMB), a glass micro bubble (GMB), or KMnO₄. 